The goals of this proposed project are to identify risk factors for prostate cancer, to identify specific genetic and biochemical markers associated with prostate cancer, and to identify relationships between risk factors and biomarkers. The study will utilize a case-control design. In-person interviews will be used to collect data on prostate cancer risk factors such as race, family history, medical history, diet, alcohol, tobacco use, and occupation (including farming-related exposures). Blood samples from cases and controls and tissue samples from cases will be analyzed for biochemical and genetic markers hypothesized to be associated with prostate cancer. The following specific hypotheses will be investigated: (1) Increased intake of dietary fat, pesticide exposure, farming, family history of prostate cancer, or race are associated with prostate cancer risk. (2) Certain genetic markers are associated with increased frequency based on exposure variables leading to an increased risk of prostate cancer. (3) Farming and occupational pesticide exposure are related to increases in the frequency of loss of heterozygosity of chromosomes 8, 10 , and 17. (4) High levels of dietary fat intake are associated with high androgen levels. Cases will be all Minnesota and Wisconsin incident men diagnosed with prostate cancers, aged 80 or less, over a two-year time period. An equal number of controls will be selected from state driver's license records and frequency matched to cases on age and state. Cases and controls under the age of 60 will serve as the primary group of interest although all cases will be compared to all controls.